Introduction: The species we have chosen is Prosopis africana (Guill. & Perr.) of the Fabaceae family is a medium-sized shrub that can reach about 30 m in height and is widespread in tropical Africa, locally known in the Central African pharmacopoeia. It is a species widely used in traditional medicine for its therapeutic properties. Objectives: As part of the valorization of medicinal plants used in the Central African pharmacopoeia, the interest of this work is focused on ethnobotanical investigations, chemical screening and antioxidant activity of Prosopis africana. Methods: Four solvents of different polarities were used (cyclohexane, dichloromethane, acetone and methanol) for extraction. Qualitative analyses were based on staining reactions, followed by quantification by the 96-well plate reader to determine polyphenols, tannins, flavonoids and anthocyanins. Results: The extraction results showed that the methanol extract has the best yield of 14.45%. Qualitative analyzes revealed the presence of tannins, flavonoids, sterols, triterpenes and saponosides. The polyphenol content was better than the other families of compounds quantified (Table 2). It varies between 42,90 and 247.89 mg of gallic acid equivalent (EqAG) /g. The methanol and acetone extracts have strong antioxidant activity. They have respectively the percentages of inhibition of DPPH the values ​​98.47±00.70 and 98.55±00.10% (Figure 5). Principal component analysis (PCA) was performed using the «FactoMineR» and «factoextra» packages of the R software circle of variable correlation. The best Person (r) correlation coefficient obtained was 0.95 between polyphenols and DPPH inhibition. Conclusion: The phytochemical study revealed the presence of certain molecules such as polyphenols and alkaloids, which can give Prosopis africana (Guill. & Perr.) its therapeutic properties.

This study carried out on the methanol extract from the bark of the Manilkara mabokeensis plant, in order to determine the active principle and its effect on the strains of Staphylococus aureus, Shigella sp and Escherichia coli. Two methods of antibiogram (dilution and diffiusion) were used. The methanol of diffusion in solid medium (Mueller Hinton), induced growth inhibition diameter of 20mm, on E. coli and Shigella sp, respectively. However, the S. aureus brain multiplied around the plant extract disc. For the dilution method, the minimum inhibitory concentration was 0.07 for E. coli and 0.09 for Shigella sp. Therefore the extract of the plant was found to be active with a bactericidal effect for E. coli and bacteriostatic effect for Shigella sp. Chemical screening revealed the presence of tannins, flavonoids, the power and quinones. These results confirm the use of this plant to treat some cases of infections observed in the traditional workplace.